| Summary: | Includes bibliographical references === The Benguela Jet is a north-westward flowing current in the southern Benguela region. It is known to have an important influence on the fish recruitment yet little is known about the physical properties of the jet. In this study the ability of satellite data (SST and altimetry) to resolve the Jet was investigated. Following this, the annual cycle of the Benguela Jet was investigated using monthly climatological means computed from both remotely sensed and model output data (from the Regional Ocean Modelling System). Two altimeter tracks were identified as best suited to study the Benguela Jet: the Topex-A / Jason-1A Track number 209 which crosses the Benguela Jet current in its northern region off the Cape Columbine and the Topex-B / Jason-1B track number 31, which crosses the Benguela Jet current in the southern region. The month of January and July were chosen due to the fact that they represent the peaks of summer and winter. The surface geostrophic currents derived from both the model and satellite data reproduced the existence of the jet current off Cape Columbine and the Cape Peninsula. The jet was narrow and strong in January off Cape Columbine and off the Cape Peninsula and was situated farther offshore based on the model, relative to the altimeter data. Outputs from the numerical model showed that in July the jet was confined to the coast and was stronger off the Cape Peninsula (0.5 m.s-1) compared to Cape Columbine (0.4 m.s-1). A comparison between the regions of strong velocity gradient and the position of the upwelling front were in agreement in depicting the position of the jet. Altimetry, which suffers from imitation in coastal regions, could not reveal the jet in July due to its proximity to the shore at this season. The offshore boundary of the jet is resolved by altimetry in January. The interannual variability of the Benguela Jet has been identified.
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